OS X Yosemite Keeps Crashing To Log-In Screen

I have two MBA, Little Snitch installed only at home (daemon consuming about 35MB). Crashes to log-in screen experienced only at work (no Little Snitch).

I would see relation rather somewhere in this direction - https://medium.com/@mariociabarra/wifriedx-in-depth-look-at-yosemite-wifi-and-aw dl-airdrop-41a93eb22e48 .

Still experiencing this problem. I've lost count of how many times this problem has occurred. I'm running any of the software which has been suggested as causing the problem. I've also only experienced this issue since upgrading to Yosemite. I was about to try and reinstall and see whether the problem persisted - but it sounds like this won't fix anything and will just be a waste of my time.

The quality of Yosemite is shocking - I've experienced so many bugs since upgrading from weird screen flashing through to weird behaviour with external monitors. To be honest it's not acceptable to be having this many problems with a 4 month old $1800 laptop.

I think I'm going to move back to Mavericks when I have time to do a fresh install.

Just curious to know if anyone is running Avast Antivirus for Mac.

I removed it a week or so ago, and have not had any more crashes.

I'm betting this is not caused by a buggy 3rd party app. This is just a nasty, hard to replicate bug in Yosemite.

Judging from the number of possible apps (suggested in this thread) that this could be caused by I'm guessing it's none of them. Even if this was caused by a 3rd party app (which I'd place money on the fact it's not), Yosemite should handle the problem in a much better way.

For example the first response should be show the process as not responding, if this is not possible, terminate the app, not the user session. And if for some highly unlikely reason it does require the user session to be terminated, provide the user with some information about what has just happened so that they can troubleshoot and fix the problem.

This whole thing just stinks! It's the kind of behaviour I'd expect back in the days of OS 9, but not from a modern OS with memory protection!

Follow up - Little nitch

Some more details.

With a single user, it seems to behave.

The problem appears with more than one user logged in.

My Set up

User 1 auto-logs in and runs iTunes serving media for the house.

User 2 is me working.

User 1 - 'Little Snitch Network Monitor' is now at 3.03 GB (And climbing) after 2 days running.

User 2 - 'Little Snitch Network Monitor' is at 44.5 MB (Normal operation).

Me thinks we have a memory leak..

I don't think Litttle Snitch is the cause of the problem, certainly not in my case.

I'm not running Little Snitch, or using multiple user accounts on my Mac.

Besides, memory leaks shouldn't cause this kind of behaviour - I've seen them in the past with browsers (Firefox used to be notorious for this) and it just resulted in the system gradually becoming a bit sluggish and then the app eventually becoming unresponsive and crashing.

I had a week without a crash. Today I have disconnected my MBA from external monitor, ethernet over USB and power cord all at the same time - and crash was back here. In my case it is definitely somehow related to the external monitor.

Just curious, in the split second before the crash, do you see the monitor (laptop or external) colors change? I click on something, get a slight pause, the color calibration changes, and then I get booted to the login screen.

I seem to experience that - it's more display flashing and a weird sort of graphics tearing. I also use an external monitor on a regular basis.

I too use an external monitor and have noticed the crashes generally occur after I've been onsite and plugged back in to the external via my Thunderbolt/MDP. However, I had done this multiple times before the most recent crash so it's definitely intermittent. In fact, I have noticed that since my last crash and login the weird distortion of my overlay graphics (volume, device connection etc.) is still present, yet the OS is otherwise stable! Could this all be a graphics/driver fault?

StevePW - that's exactly the kind of thing I'm seeing. I'm pretty convinced it's something to do with the graphics drivers in Yosemite...

I have not had the crash in many days now - 5 approx. I'm avoiding running Messages as I said in earlier post. That was my only new app of lately - as I didn't use prior to Yosemite.

I do not have any third party apps installed or running - except for Transmit (rarely used), Office (used daily), Parallels(tested once recently - otherwise rarely).

I do have most Apple apps and they are used daily - including Xcode, fcp, pages, remote desktop...mail, cal etc.

I have tested running all my apps - and although it all gets very slow and spinning wheel of death shows up mostly...eventually I can interact with all apps...and eventually close all down etc...

I have not done any PRAM reset or similar - except for Disk Utility check of disk. And have not reinstalled or anything major.

Again - I'm no longer running Messages!! - and have not seen the crash to login for many successive days now. Will report back if this changes.

Jules.

It definitely seems to be graphics drivers related. I can make it happen every single time I connect one of my external monitors using a dvi to mini display port adapter. Here's a video:

https://www.youtube.com/watch?v=hMlYStjNOSQ

It occasionally happens at work disconnecting or connecting my 27" thunderbolt display, but much less frequently.

Further to my above post, recently noticed that in "About This Mac" it said "(null) (null)" next to Graphics and "16 GB ???" next to Memory. Restarted and it's gone back to normal...something definitely amiss here though.

I did not notice this, but you may be suffering from this? http://www.macissues.com/2014/11/04/transparency-and-graphics-switching-in-yosem ite-affecting-macbook-pros/